Preheat oven to 350°F. Unfold pastry sheets onto a lightly floured surface and cut each into strips about 1" wide. Weave strips into a lattice crust. Transfer to a baking sheet coated with cooking spray. Lightly brush top with beaten egg/water. Bake for 25 minutes. Remove and set aside.

For the blackened chicken...

Mix dry seasoning and toss with chicken pieces. Heat a cast-iron skillet or dutch oven to medium-high heat. Add 1 tablespoon each of butter and canola oil to the pan and add chicken pieces in batches, searing on all sides. Reserve cooked chicken pieces.

For the pie filling...

Reduce the heat to medium and add butter to the skillet. Add the carrots, onions, and celery and cook for 5 minutes or until the vegetables are tender-crisp, stirring occasionally. Add the flour and cook for 3 minutes. Gradually stir in the broth and milk and heat to a boil. Cook and stir until the mixture boils and thickens. Add additional liquid if too thick.

To assemble...

Stir in the blackened chicken and 3 tablespoons parsley. Pour mixture into a 9"x9" baking dish. Top with lattice crust, trim excess edges. Place the casserole onto a baking sheet. Bake for 20 minutes or until the filling is hot and bubbling and the pastry is golden brown.

Recipe by Lemony Thyme at http://www.lemonythyme.com/blackened-chicken-pot-pie/